A variety of techniques, including electron microscopy, light microscopy, protein chemistry, enzymology, and immunochemistry, will be used to study the fundamental mechanisms underlying flagellar motility in sea urchin sperm. The various ATPase proteins in the flagellum will be isolated, and their function studied in relationship to the mechanisms responsible for inducing and for coordinating the sliding between tubules to produce coordinated bending waves. Anti-dynein serum will be used to study the mechanism by which dynein interacts with the tubules and ATP to produce active sliding.